<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .comment {
            width: 300px;
            height: 100px;

            /* 不允许拉动大小 */
            resize: none;
        }
    </style>
</head>

<body>
    <!-- bug 此标签是双标签 --- 使用的时候 不要换行 -->
    <textarea class="comment"></textarea>
    <h1>111111111</h1>

</body>

</html>